For $35 you can get him this Palight C9 with an XP-G R5 along with the battery and external charger. It will put out a good 300 lumen and with enough modes for any situation. Decent throw with the C9 reflector for finding the dog in the fields and lots of spill for walking the road.
I personally don't like the idea of internally charged lights as it is difficult to monitor the battery while it's charging and it is a couple more things to go wrong with the light at some point down the line. The cover for the plug hole can get lost, the charging socket in the light can develop a bad connection, the charging circuit can quit all together leaving it useless unless one has an external charger or, in a worse case scenario, could go bad and overcharge creating a possible fire/explosion risk.
JohneyMac has a point that I did not think about. His idea is better than mine overall. That is why I am still learning and others on here are the pros. :)
A 2xAA flashlight is a good choice for someone who is not into flashlights like most of us on this forum.
I had a Fenix LD20, and sold it to a someone that was looking for a flashlight, also to use when walking the dog. He is using it for 2 years (with nimh's) and he is still very pleased with it.
There is not that much choice in decent 2xAA flashlights, most of them are 1xAA with an extender to fit two batteries. Fenix has some very good 2xAA flashlights, but they are not cheap...
I recently gave my brother a Solarforce L2i with a 3-mode XP-G drop-in. I included AAA NiMH's and the inexpensive Sony charger that charges cells independently so he could charge the odd number of batteries. If throw wasn't as important, I've also given away iTP A3's which are impressive due to the small size, but too floody for anything more than 30 feet or so. 3 AAA batteries don't have a huge amount of life, but not bad, and they're rechargeable. I don't think I'd want to run a XM-L with AAA's though.
In the budget category, AA lights are just not that good. Even a non-enthusiast can appreciate the power of an 18650 but even more so, the fact that they won't have to buy another battery for a couple years. If it was a light for just around the house or hunting for something in the shed I'd recommend an AA light but for spotting in the fields and dog walking I'd go stronger. Just my opinion and as such not worth anything more than another.
How about a Trustfire R5-A3 every one who sees one is blown away by what a AA battery can produce for light. Plus KD has the one with the modable driver for $14bucks.
For throw w/ AA, the ultrafire c88 looks the light to get. I was trying to figure out if it's regulated as that would be best for alkaline/nihm usage. DD might be erratic w/ different batteries.
It is a quite bright one in the AAA competition. I tried the same drop-in with 2xAA also. Acceptable but not as bright as 3xAAA in a L2i. Always advise to get a P60 as a first light. Has great expansion ability and gives a balanced throw - flood as a utility light.
I'd say it's hard to beat SF L2r + low voltage 3-mode XPG R5 dropin with OP reflector. Not the chepest alternative, as they are 25$ combined, but very good quality and nice looking light. Especially in silver. And maybe with another bezel, that stock one is too aggressive to my taste. I did one for a friend where I put the L2X standard bezel I had laying around and replaced the emitter with neutral R4 and he has been very impressed with the light.
Mcu_C-88...3AA's feels like a tank beautiful bezel tons of throw ..Nobody doesn't like this light .it feels like 100$ flashlight and takes off the shelf AA's if that's all you have .
*Always remember you're unique just like everyone else.
If you're not against modding, a great option would be to make your own light for him. I did this recently so I could have lights to gift to relatives. This is what I used:
1x Wootlite
1x XM-L
1x 4.2-8.4v 3A 3mode driver
3x 3AA battery holders
1x UCL 40mm lens
What one ends up with is a 2D mag sized flashlight (smaller head), that will put out over 800L on 6 AA alkalines for @$30. Everyone should experience the joy of a well driven XM-L :)
This reminds me...I really need to update the original post with this build.